Gas generator



Feb. 17, 1948.

N. K. KO EBEL GAS GENERATOR Filed Sept. 21, 1942 GAS BLEEDER CHARGING CHARCOAL HOPPER mow R 0 0 D T m m L C AIR INLET Patented Feb. 17, 1948 UNITED STATES PATENT OFFICE GAS GENERATOR Norbert K. Koebel, Oak Park, 111., assignor to Lindberg Engineering Company, Chicago, 111., a corporation of Illinois Application September 21, 1942, Serial No. 459,153

7 Claims.

This invention relates to gas generators and more particularly to apparatus for generating a gas to form an atmosphere in a heat treating furnace or the like.

As heretofore generally constructed, gas gencrating apparatus of this type has comprised a vertical casing with a combustion chamber in its lower part and a hopper in its upper part. In use, charcoal or the like has been burned in the combustion chamber, a part of the combustion gases being withdrawn at the upper part thereof and the other part of the gases rising through the hopper to remove water vapor and volatile constituents from the charcoal.

Because of the high temperature in the combustion chamber a great deal of difliculty has been encountered in sealing the space around the chamber against air leakage. When air leakage at this point occurs the air becomes mixed with the gases going to the furnace, altering the constituency of the gases and resulting in a less desirable atmosphere in the furnace.

It is accordingly one of the objects of the present invention to provide a gas generator in which mixture of air with gas going to the furnace is positively prevented.

Another object of the invention is to provide a gas generator in which a, portion of the gas is withdrawn and mixed with air leaking around the combustion chamber and a second portion i-swithdrawn for use in the furnace. According to one feature of the invention a third portion of the gas is conducted through a fuel hopper to remove water vapor and volatile constituents from the fuel and is then mixed with the first withdrawn portion of the gas and burned.

Still another object of the invention is to provide a gas generator which is relatively simple and inexpensive to construct, is sturdy and rugged and functions efliciently to produce gas of the desired constituency.

The above and other objects and advantages of the invention will be more readily apparent from the following description when read in connection with the accompanying drawing, in which the single figure is a side elevation with parts in section of a gas generator embodying the in-' vention.

The generator shown in the drawing comprises a cylindrical shell of sheet metal or the like having a lower portion Hi and an upper portion H connected by circular flanges l2. The lower portion Iii carries a horizontal perforated partition 13 forming in the lower part of the casing an air inlet chamber 14 having a supply conduit l5 through which air may be supplied under pres sure. At one side the air chamber is formed with a clean-out door 16 for removal of ashes and the like. While the partition [3 has been shown as a single fixed plate, it will be understood that any desired type of fixed or movable grates could be used.

Above the partition 13 there is mounted a tube 11 formed of fire resistant material and of smaller diameter than the casing in. The space be-' tween the casing and the tube is filled with a sealing material such as heat resistant cement l8 terminating flush with the top of the tube l1.

Above the tube I! there is mounted in the-casing an inverted conical bafile l9 formed of sheet metal or the like having a circular flange fitting between and supported byvthe casing flanges E2. The central portion of the bafile I9 is open and is formed with an annular skirt 21 extending down into the tube l1 and spaced therefrom to leave an annular outlet opening 22 from the tube l1 into the space below the baille l9. It will be noted that this space is in open communication with the sealing material 18 so that any air leaking therethrough will enter the space. The space below the baffle l9 communicates through a serites of ports 23 in the casing wall with an annular manifold 24 around the casing.

Above the baffle IS a second inverted conical baffle 25 is supported in the casing as by means of a welded flange 26. The central portion of the baffle 25 is openand carries an annular depending skirt 2! with substantially the same diameter as the skirt 2|. The skirt 21 is of such a length as to leave an annular outlet opening 28 therebelow communicating with the space between the baffles which is in turn connected with an outlet conduit 29 leading to a heat treating furnace or the like.

The space above the baffle 25 forms a hopper and is closed by a cover 3| secured to the upper edge of the casing part I I. The hopper is formed with a, filling door 32, has a gas outlet conduit 33 communicating therewith. As shown, the manifold 24 is connected. to the conduit 33 by a pipe 34 which in turn communicates with a waste gas burner 35.

In operation, I have found that the cement I8- It will be 3 noted that there is very little possibility of air leaking from the cement 58 into the combustion chamber formed by the tube I 1 since the pressure is normally higher in the combustion chamber than in the body of the cement due to greater resistance to flow through the cement.

With the present apparatus, any air leaking through the body of cement is will be mixed with gas flowing through the annular outlet op'en ing 22 and will flow with such gas into the manifold 24 and through pipe 34 to the burner 35. Gas withdrawn through the opening 28 for use in the furnace, therefore, can have no air mixed with it and will go to the furnace in the desired condition without any pollution. The gas flowing up through the sleeve 21 will flow through the charcoal or like fuel stored in the hopper and eventually will pass out through conduit 33 to the burner 35. t

The present invention thus provides a generator in which mixture of the gas with air, or pollution by other means is positively prevented so that a very-clean gas whose constituency can be accurately controlled is provided.

While one embodiment of the invention has been illustrated and described in detail, it will be understood that this is illustrative only and is not to be taken as a definition of the scope of the invention, reference being had for this purpose to the appended claims.

What is claimed is:

1. A gas generator for heat treating furnaces and the like comprising a vertical casing having an air inlet chamber in its lower portion, a vertical tubular member of smaller diameter than the casing above the air inlet chamber forming a combustion chamber, sealing means around said member sealing it in the casing, an inverted conical bailie secured in the casing above the sealing means and spaced from the tubular member to form an outlet opening to the space below the baffle said balile having a central opening therein, a second inverted conical baffle above and spaced from the first baflle having a central opening therein, an outlet conduit communicating with the space between the baflles, and anoutlet conduit communicating with the space below the first baille.

2. A gas generator for heat treating furnaces and the like comprising a vertical casing having an air inlet chamber in its lower portion, a vertical tubular member of smaller diameter than the casing above the air inlet chamber forming a combustion chamber, sealing means around said member sealing it in the casing, an inverted conical baffle secured in the casing above the sealing means and spaced from the tubular member to form an outlet opening to the space below the baiiie said baiile having a central opening therein, a second inverted conical baille above and spaced from the first bafiie having a central opening,

therein, an outlet conduit communicating with the space between the baiiles, a closure for the top of the casing, and an outlet conduit communicating with the space below the closure and with the space below the first baille. v

3. A gas generator comprising a vertical cylindrical casing, a horizontal partition in the lower part of the casing forming below it an air sham her, a cylindrical heat resisting tube of smaller diameter than the casing above the partition forming a combustion chamber, sealing material between the tube and the casing, an inverted conical bailie having an open center secured to the casing above the combustion chamber, a tubular skirt around the opening in the baffle projecting into and spaced from the tube to form an annular gas outlet opening from the combustion chamber to the space below the battle, a second inverted conical baffle having an open center secured in the casing above the first bafile and spaced therefrom to form a gas outlet opening between them, a gas outlet conduit communicating with the space between the baflles, and a waste gas burner communicating with the space below the first bafiie.

4. A gas generator comprising a vertical cylindrical casing, a horizontal partition in the lower part of the casing forming below it an air cham her, a cylindrical heat resisting tube of smaller diameter than the casing above the partition forming a combustion chamber, sealing material between the tube and the casing, an inverted conical baflle having an open center secured to the casing above the combustion chamber, a tubular skirt around the opening in the bafile proiecting into and spaced from the tube to form an annular gas outlet opening from the combustion chamber to the space below the baffle, a second inverted conical bafile having an open center secured in the casing above the first bafile and spaced therefrom to form a gas outlet opening between them, a gas outlet conduit communicating with the space between the baffles, a closure for the top of the casing forming a hopper above the second baffie, and a waste gas burner communicating with the hopper and with the space below the first bafile.

5. A gas generator for heat treating furnaces and the like comprising a vertical casing having an air inlet chamber in its lower portion, a vertical tubular member of smaller diameter than the casing above the air inlet chamber forming a combustion chamber for producing gas, sealing means around said tubular member sealing it in the casing, an annular baflie having a central opening registering vertically with the tubular member and secured in the casing above the sealing means and spaced from the tubular member to form an annular opening between the tubular member and the baifle which is small relative to the central opening, an outlet conduit communicating with the space between the baffle and he sealing means for conducting mixed gas and leakage air from the casing, a hopper above and spaced from the annular baflle arranged for feeding fuel to the combustion chamber through the central opening of the annular bailie, and an outlet conduit communicating with the space between the baffle and the hopper for conducting gas from the casing.

NORBERT K.KOEBEL.

REFERENCES CETED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

